SwissBioisostere provides access to our knowledgebase of molecular replacements, useful for compound optimization in drug design.

Two types of queries are suitable :

• you are interested in a range of possible replacements for a single substructure
  ( e.g. replacements for an amide group )
• you want to know details about a particular substructural replacement of interest
  ( e.g. carboxylic acid vs. tetrazole )

Depending on your question, please enter either one or two substructures of interest in the substructure box below and select Query Database.

For a replacement A->B query, please indicate attachment point in your substructures drawings by adding R-groups R1-R3 at the corresponding location in each o f the query structure.

Examples can be found here.

Ref.: Wirth, M., Zoete, V., Michielin, O., & Sauer, W. (2013) SwissBioisostere: a database of molecular replacements for ligand design, Nucleic Acids Research, 41 (D1), D1137-1143.

Fragment 1		Fragment 2
SMILES		SMILES